Refinement — minimizing pain, distress, and suffering in laboratory animals while achieving scientific goals — is both an ethical obligation and increasingly a scientific requirement for valid research.
Laboratory animal refinement represents a welfare imperative grounded in both ethics and science. Animals experiencing uncontrolled pain or distress produce stress-altered physiological data that compromises experimental validity. Better welfare therefore serves scientific quality as well as animal interest. Refinement advances include using appropriate analgesics, setting humane endpoints that end experiments before severe suffering, providing environmental enrichment, and training animals to cooperate with procedures rather than requiring restraint. The scientific and welfare cases for refinement are aligned, and institutions that invest in refinement capabilities produce better science with less animal suffering.